Hi Guys,
I was thinking of using the 315 MHz receiver transmitter pair. Are they FCC certified? If so, do you need to show a certificate? The modules are here:
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Thanks.
I’d prefer the Hope RF RFMxx modules.
Thanks for the response.
So are you saying that these 315MHz modules are not FCC certified? I tried to look for them in chapter 15? of the FCC manual and I could not find it.
I prefer to use these modules because of the fast learning curve and simplicity.
They are obviously not FCC certified.
I don’t believe modules can be FCC certified, as the mounting and antenna type have a lot to do with radiation characteristics of the finished product. Also, the duty cycle of the product in transmit is highly regulated at 315 and 434 MHz. Certification can run up to 100K per product.
Ron
Yep. You have to certify a whole module. Case in point, digi’s XBee’s are all FCC certified. They have the whole chabang. 
Why would you consider the Xbee to be a “module” that can be FCC certified but not the Laipac or Hope RF products? I think the Xbee can be FCC certified is because it’s frequency is in a valid U.S. ISM band, not because it is a “module”. I don’t think 434 Mhz is ae valid part 15(unlicensed radio frequency device), 18(ISM) or 90(private land mobile radio service) bands and it would appear to be illegal to operate them in the U.S. irregardless of whether they were “modules”; unless you have a license to operate at that frequency.
p.s. please point me to a section of FCC CFR regarding “modules”; -thanks.
groggory:
Yep. You have to certify a whole module. Case in point, digi’s XBee’s are all FCC certified. They have the whole chabang.
many modules or “radios” are US FCC type certified. To wit, all the WiFi stuff. XBee’s have type certif. in quite a number of countries. The regulations on whether you can alter the antenna without invalidating the type certification vary around the world. And sometimes, they vary by band. We’re speaking, of course, about unlicensed band radios. Indeed, in some countries, there are now prohibitions of the use of 2.4GHz outdoors. As if RF will obey the bounds of windows and walls.
Let’s not confuse a unlicensed radio band and a uncertified radio design. The reason unlicensed bands can exist is because the radios operating there are certified by the designer to have met FCC (or applicable country) requirements. That cell phone, FMS radio, wifi modem, keychain remote etc. all should have an FCC id# (in the US) on them that says by design, your operation of them won’t violate the legal requirements to radiate at that frequency, in that unlicensed band. That’s a big difference from someone using some mystery thing they designed or obtained somewhere that operates in an unlicensed band being able to legally radiate in that unlicensed band. People who want to radiate RF of noncertified devices do so in a anechoic chamber, get experimental authorization from the FCC (in the US) or get a amateur radio license and radiate in a band set aside for that.
I saw nothing on the wireless module pages that said anything about needing a lic. in order to operate the modules in the 314 and 433 Mhz freq. What I’m reading here is that I CAN’T. So, are there any rf modules anywhere that I can use for short range that don’t have to have a blasted lic? I can get one. I just took the ARRL tech. prep test and would have passed it if I hadn’t been reading to fast.
I just spoke with a HAM. That freq. band is shared. HAMs can use higher power. You don’t need a lic. to use the modules, as long as you don’t modify it from it’s intended design. If it’s designed for a straight wire ant. then that’s what you have to use. 8)
Yes, much more sophisticated.stevech:
I’d prefer the Hope RF RFMxx modules.
FCC type certification: check the vendor's spec sheet. Often, these kind of modules are not certified because they are embedded and the antenna is user defined.RFGuy:
Hi Guys,I was thinking of using the 315 MHz receiver transmitter pair. Are they FCC certified? If so, do you need to show a certificate? The modules are here:
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http://www.sparkfun.com/commerce/product_info.php?products_id=8947#comments
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Note that in 315 and 433MHz, in the US, there are stringent transmitter duty cycle limits, and power limits. Much less so in 902-928 and 2.4GHz. In the lower frequencies, cheap things like garage door openers, wireless thermometers, etc., do not “listen before transmitting” (CSMA/CA or CCA). Therefore, to minimize interference, the FCC limits transmitter duty cycle if CSMA/CA isn’t used in these cheap devices.
Maxim Integrated Products has a pretty good write up on the 315-433 band and the FCC.
http://www.maxim-ic.com/app-notes/index.mvp/id/3587
The bit that SF sells isn’t FCC certified for reasons already noted - you don’t license a transmitter (or receiver) alone, you license the whole device.
From what I can tell it is perfectly legal to buy, sell, own and use these transmitters as long as you keep the power low. Exactly what “low” is depends on a myriad of things, some of which are listed at the link above.
XBee and type certifications: See Digi’s web site. They list all the countries in which they have achieved certification. E.g.,. in Japan and France, the radiated power is quite limited as compared to the US. Same irregularities in regulations around the world exist for 2.4GHz.
Severe duty cycle limitations in sub-GHz bands, esp. 315 and 433MHz. Not so much in 902-928MHz but even this band is much more regulatory-restrictive than 2.4GHz.
Hi Steve - I’m sure you’re right (you sound like you know a LOT more than I do on the subject!). What I and others really want to know is exactly what is or isn’t legal to do with these things. While I realize there aren’t exactly FCC police that will come get you if you build something that uses these, I’d like to stay within whatever regulations apply.
I know it’s complicated and the regulations have everything to do with power, antenna, etc, but is it safe(ish) to say that as long as you keep power low (and I realize that’s subjective), we’re OK?
If this is for hobby/experimental purposes, not commercial, then perhaps you should follow the spirit and intent of the regulations for unlicensed spectrum. It's all about sharing, not hogging. If you transmit very frequently, as does 802.11 and some uses of 802.15.4, then use CSMA/CA (listen before transmitting). In the 450MHz and lower bands, cheap hardware, transmit-only hardware, cannot do CSMA, therefore the regulations and courtesy says don't transmit often. It's all common sense.MitchV:
Hi Steve - I’m sure you’re right (you sound like you know a LOT more than I do on the subject!). What I and others really want to know is exactly what is or isn’t legal to do with these things. While I realize there aren’t exactly FCC police that will come get you if you build something that uses these, I’d like to stay within whatever regulations apply.I know it’s complicated and the regulations have everything to do with power, antenna, etc, but is it safe(ish) to say that as long as you keep power low (and I realize that’s subjective), we’re OK?
But technically, you must follow the regulations. The most important things are low power and use only frequencies set aside for public/unlicensed use. Don’t interfere with an important radio service, and don’t jam out your neighbors’ garage door openers or wireless thermometers!
To add a little to Steve’s comments above.
Even if you had the module and product certified it would be under the FCC Part 15 rules. This requires that the product may NOT interfere with Any licensed radio service and MUST accept interference with any licensed radio service.
So if your unit does cause interference the FCC will do something if they receive a complaint.
Hi Steve, thanks again for posting on the subject. However, and with all due respect, it isn’t common sense, at least not to a lot of hobbyists (like me) 
I’m using some of these modules to talk to PIR sensors and never thought about FCC regulations for one second when I first wired everything up. The power is pretty low in my opinion and it only transmits when the sensor goes off (which ends up being about 10 times per day).
Hmm…good thing I found this post. I’ll make sure to run the output of the transmitter that I buy through some massive non-utilitarian RF Amplifier. That’ll teach the FCC for confusing countless people about the differences between SMAs and RPSMAs. That and it will interfere with the guy at the desk next to mine’s project. AHH HA HA HA!
At the risk of once again being the voice of dissent, I have to say that unless you show me a FCC CFR part xxx paragraph that states emissions below a certain power level are uncontrolled at that frequency in the U.S. when transmitted by an uncertified device then they ARE. I know of no such definition of “low power”. FCC CFR part 15 and part 18 list the requirements to have a certifiable device design to submit to the FCC for an FCC ID # for the end user to be exempt from licensing. Just because YOU think you meet those requirements does NOT mean you can use your device without either user licensing or device certification. That’s up to the FCC. You may use a hobby 315Mhz transmit module for years without any complaints from licensed users of that band or may immediately be reported to the FCC, as was the gentleman who according to the FCC’s enforcement webpage imported and used 434Mhz wireless links in the U.S and was fined $11,000. Note that 434 MHZ is one of the freq that sparkfun sells; (and in the U.S. is regulated for licensed amateur use). And that’s just the tip of the iceberg. Over and above the hardware requirements (frequency, power level, bandwidth, spectral purity) there are band restrictions for the type of modulation (AM,FM, PSK, OOK,) and whether the transmission is phone(voice) or data authorized on that frequency.
for more info on those who thought they didn’t need approval to transmit see:
http://www.fcc.gov/eb/Welcome.html
http://www.fcc.gov/eb/Orders/2005/DA-05-2394A1.html
the FCC is prosecutor, judge and jury in these cases.
…and here’s a little chunk of a typical FCC “notice of apparent liability” (aka NAL)
radio station on 87.9 MHz from Lakeland, Florida, but states that he
did not intend to violate the Rules. Mr. Grover states that he thought
he was operating a low power FM station pursuant to Part 15 of the
Rules. However, because he did not use equipment certified for Part 15
use, Mr. Grover states he was unaware that his station exceeded the
allowable Part 15 output power. Mr. Grover also states he had no way
to verify that his equipment was set at the proper output power.
operate his station, that belief was mistaken. Part 15 of the Rules
sets forth conditions under which intentional radiators may operate
without an individual license. However, if intentional radiators fail
to comply with all of the applicable conditions set forth in Part 15
of the Rules, they are not authorized to operate in the United States
without a license. Mr. Grover admits that he did not use a transmitter
certified for Part 15 use and that he exceeded the allowable Part 15
output power. Accordingly, his operations were not consistent with the
requirements of Part 15 and were unlicensed. Moreover, his belief that
his actions did not violate the Act is irrelevant as to whether his
violation was willful, as he intentionally operated the station. Thus,
based on the evidence before us, we find that Mr. Grover willfully and
repeatedly violated Section 301 of the Act by operating radio
transmission apparatus without a license on October 2 and 7, and
November 6 and 7, 2008.
If you think saying well sparkfun sold them to me, or a guy on a internet forum said it would be OK because it was “low power” is a viable defense, good luck to you on that. And while an output power level that gets someones attention is the usual cause for investigation as it can be done outside your property, Output power is NOT the only criteria for Part 15 (or 18) compliance. Hence using CERTIFIED part 15 devices.